On immigration, the Republican Party knows it has a serious problem: their rhetoric and policy on the subject has been a factor in their consistently-worsening numbers with Latino voters. Although George Bush was able to win large numbers of Latino supporters, his outreach marked the last time that Republicans were able to connect. While there are Republican state policies which are undeniably anti-immigrant and harm Latino communities, like SB 1070, having the national leadership tend to the rhetoric and lead on the debate is a start to bridging the large schism that has been allowed to develop between Latinos and the GOP. This gap, however, has developed around rhetoric, political culture and policy, and will be difficult to mend. Today, Marco Rubio is the most visible (and only high profile) Latino in the Republican Party. While he was elected by an increasingly-fringy Tea Party, he has an opportunity now to solidify not just his own new voter base, but also the GOP's new place in today's political debate.
About his book on immigration, Jeb Bush said "The book was written last year in a certain environment... When we were working on this, Marco Rubio wasn't for a path to citizenship." When saying this, Bush was trying to explain why he had changed his mind since he wrote his book and come out against a pathway to citizenship for DREAMers. Although his quote is true, it more importantly highlights a difference in two high profile Republicans: both are running from previous statements, but one towards Latino voters that he would need in 2016, and another away from them.
Bush is making a vital error in his political calculations with his decision. Consider voter outreach organizations like Voto Latino and the press that the Latino vote got as one of the pieces of the coalition that elected Obama against Romney's nearly all-white, Mad Men vote. These organizations will be registering Latinos to vote right up until the next election. The publicity of the power of the Latino vote and how it benefits Latin Americans, meanwhile, has helped to change the culture of a group that has traditionally been less enthusiastic about the voting process.
Consider also that the Latino voter demographic, following every prediction of both demographers and politicians, will continue to grow (especially if immigration reform is pushed through and more Latinos are drawn to the country and given citizenship). This shouldn't be much of a stretch of the imagination: the last election was the natural outcome of a demographic shift in our country that many politicians have feared and tried to institutionally block with harsh immigration and cultural laws (i.e. the State of Arizona banning Mexican-American Studies in public schools) for years.
At the moment, Marco Rubio is the only rising star that the Republican Party has who could uniquely address this situation. Rubio is also their only "rising star" in general other than Rand Paul and Chris Christie. For him, this represents a great opportunity: to shore up a new base now that the Tea Party caucus is now dead.
Michelle Bachmann's recent rant on Obamacare, giving credence to the charge that all House Republicans do is rant and try to repeal Obamacare, is a wonderful example of the sort of extremist, hyperbolic, alternate-reality bubble the Tea Party built that popped so violently on election night Karl Rove needed a fresh pair of jockeys after: "Let's repeal this failure before it literally kills women, kills children, kills senior citizens. Let's not do that. Let's love people. Let's care about people."
Aside from being so reductionist that even the mental pygmies that constitute the loudest voices in the Tea Party would have a difficult time not being intellectually insulted by Bachmann's statements, this is exactly the character that Marco Rubio does not want to be drawn as if he wants a long career in politics outside of cornering an obscure, crazy electorate like Bachmann.
Rubio leading on immigration could also be the jolt that the Republican Party needs: right now, it's still in Bachmannland where Herman Cain was the famously reductionist ("9-9-9") pizza-man frontrunner whose non-consensual "grabbyness" led to enough women coming out against him on sexual harassment he was forced out, before leading to a life of regular (as opposed to unintentional) comedy as a recurring Daily Show segment. His suggestion of an electrified border fence, amongst all the rest of the insanity of the primary season, hasn't faded from memory, even if Mitt Romney is vanishing rather quickly. So far, the Republican Party still hasn't fully escaped this, and neither has Marco Rubio.